此方法对于两种底物都有很好的普适性。常见的苯甲醛或杂芳基甲醛与脂肪醛酮都可以高产率的进行反应。
反应机理
操作步骤
General Procedure A:
To a solution of tosylhydrazide (1.0 equiv.) in MeOH (0.5 M) was added
aldehyde/ketone (1.0 equiv.). The reaction mixture was stirred at room temperature until complete conversion was observed by TLC. Solvents were removed in vacuo to give the Tosylhydrazone compound.
General Procedure B:
Tosylhydrazone (0.5 mmol, 1.0 equiv.), Cs2CO3 (0.75 mmol, 1.5 equiv.) and aldehyde (if a solid at room temperature, 0.5 mmol, 1.0 equiv.) were placed in a tube. The tube was backfilled with argon and evacuated (3 cycles), before addition of 1,4-dioxane (2 mL) under an argon atmosphere, followed by addition of aldehyde (if a liquid at room temperature, 0.5 mmol, 1.0 equiv.). The tube was sealed with a
silicone/PTFE cap and heated to 110 °C for 6 h. The mixture was cooled to room temperature, quenched with NH4Cl (2 mL, saturated aqueous solution) and extracted with CH2Cl2 (3 × 2 mL). The combined organic phases were dried over MgSO4 and solvents removed in vacuo to give a residue which was purified by flash column
chromatography (EtOAc/hexane) to give the title compounds.
参考资料
Org. Lett. 2014, 16, 11, 3064–3067
